/***************************************************************
  __CPU_CONTEXT.H

       This file contains CPU CONTEXT operation functions & data
       declarations.

       PART OF : CPU - library .
       USAGE   : Internal only .
       NOTE    : Include "libcpu.h" before this FILE .

       Copyright (C) 2026  by Andrew V.Kosteltsev.
       All Rights Reserved.
 ***************************************************************/
#ifndef __CPU_CONTEXT_H
#define __CPU_CONTEXT_H
#ifdef __cplusplus
extern "C" {
#endif

#define CPU_GUEST_FD_MAX  256

typedef struct __cpu_fd_entry
{
  int           host_fd;
  unsigned int  owned;
  unsigned int  flags;
} __cpu_fd_entry;

typedef struct __cpu_context cpu_context;
struct __cpu_context
{
  __mpu_uint64_t _pc;
  __mpu_uint64_t _sp;
  __mpu_uint64_t _fp;
  __mpu_uint32_t _psw;
  cpu_stop_reason _stop_reason;
  __mpu_int32_t _exit_status;

  __mpu_UNIT_t  *_program;
  __mpu_uint64_t _program_size;
  __mpu_uint64_t _program_capacity;
  __mpu_UNIT_t  *_data;
  __mpu_uint64_t _data_size;
  __mpu_uint64_t _data_capacity;
  __mpu_UNIT_t  *_stack;
  __mpu_uint64_t _stack_size;
  __mpu_uint64_t _stack_capacity;
  __mpu_UNIT_t  *_control;
  __mpu_uint64_t _control_size;
  __mpu_uint64_t _control_capacity;
  __mpu_UNIT_t  *_input;
  __mpu_uint64_t _input_size;
  __mpu_uint64_t _input_capacity;
  __mpu_UNIT_t  *_output;
  __mpu_uint64_t _output_size;
  __mpu_uint64_t _output_capacity;
  __mpu_UNIT_t  *_trace;
  __mpu_uint64_t _trace_size;
  __mpu_uint64_t _trace_capacity;
  __mpu_UNIT_t  *_heap;
  __mpu_uint64_t _heap_brk;
  __mpu_uint64_t _heap_size;
  __mpu_uint64_t _heap_capacity;
  __mpu_uint64_t _heap_limit;

  int             _fd_initialized;
  __cpu_fd_entry  _fd[CPU_GUEST_FD_MAX];

  int             _cwd_initialized;
  int             _cwd_fd;

  __mpu_UNIT_t _regs[CPU_REGISTERS_MEM_SIZE_IN_UNITS];
};

extern __thread struct __cpu_context *pcctx;

#define __PC       (pcctx->_pc)
#define __SP       (pcctx->_sp)
#define __FP       (pcctx->_fp)
#define __REGS     ((__mpu_UNIT_t *)&pcctx->_regs[0])
#define __PROGRAM  (pcctx->_program)
#define __PSIZE    (pcctx->_program_size)
#define __PCAP     (pcctx->_program_capacity)
#define __DATA     (pcctx->_data)
#define __DSIZE    (pcctx->_data_size)
#define __DCAP     (pcctx->_data_capacity)
#define __STACK    (pcctx->_stack)
#define __SSIZE    (pcctx->_stack_size)
#define __SCAP     (pcctx->_stack_capacity)
#define __CONTROL  (pcctx->_control)
#define __CSIZE    (pcctx->_control_size)
#define __CCAP     (pcctx->_control_capacity)
#define __INPUT    (pcctx->_input)
#define __ISIZE    (pcctx->_input_size)
#define __ICAP     (pcctx->_input_capacity)
#define __OUTPUT   (pcctx->_output)
#define __OSIZE    (pcctx->_output_size)
#define __OCAP     (pcctx->_output_capacity)
#define __TRACE    (pcctx->_trace)
#define __TSIZE    (pcctx->_trace_size)
#define __TCAP     (pcctx->_trace_capacity)
#define __HEAP     (pcctx->_heap)
#define __HBRK     (pcctx->_heap_brk)
#define __HSIZE    (pcctx->_heap_size)
#define __HCAP     (pcctx->_heap_capacity)
#define __HLIMIT   (pcctx->_heap_limit)
#define __STOP_REASON (pcctx->_stop_reason)
#define __EXIT_STATUS (pcctx->_exit_status)
#define __CPU_PSW  (pcctx->_psw)
#define __SET_CFLAG(mask)     (pcctx->_psw |= (mask))
#define __CLEAR_CFLAG(mask)   (pcctx->_psw &= ~(mask))
#define __INVERT_CFLAG(mask)  (pcctx->_psw ^= (mask))
#define __CFLAG(mask,shift)   ((pcctx->_psw & (mask)) >> (shift))

extern __mpu_uint64_t __cpu_heap_brk( __mpu_uint64_t new_brk );

#ifdef __cplusplus
}
#endif
#endif